Long-term Impact of Androgen-deprivation Therapy on Cardiovascular Morbidity After Radiotherapy for Clinically Localized Prostate Cancer.

Overview

abstract

OBJECTIVE: To characterize the impact of androgen-deprivation therapy (ADT) on the incidence of cardiovascular events (CE) in prostate cancer patients treated with radiotherapy (RT). MATERIALS AND METHODS: There were 2211 patients with localized prostate cancer treated with RT from 1988 to 2008 at our institution. There were 991 patients (44.8%) who received ADT at the time of RT for a median of 6.1 months. Salvage ADT was initiated prior to CE in 365 men (16.5%) at a median of 5.5 years (range: 0.6 to 18.4 years) after RT and continued for a median of 4.3 years. A nomogram was constructed to predict the 10-year risk of CE "post-RT" (i.e., after RT). RESULTS: Patients receiving ADT at the time of RT exhibited significantly higher 10-year incidence of CE (19.6%, 95% CI 17.0%-22.6%) than those not receiving ADT (14.3%, 95% CI 12.2%-16.7%, P = .005). On multivariate analysis, both ADT at the time of RT (P = .007) and the time of salvage (P = .0004) were associated with increased CE risk, as were advanced age (P = .02), smoking (P = .0007), history of diabetes (P = .0007), and history of CE before RT (P < .0001). A nomogram using patient age, smoking status, history of pre-RT CE, history of diabetes, and ADT use at the time of RT predicted the rate of 10-year CE with a C-index of 0.81 (95% CI, 0.72-0.88). CONCLUSION: While ADT is often an essential part of prostate cancer treatment, patients should be counseled regarding increased risks of CE and prophylactic efforts should be considered to mitigate that risk.